Portolan Capital Management, LLC's ownership history for BIIB

Portolan Capital Management, LLC currently holds 118.5K shares with a market value of $21.7M. It started holding BIIB on 2025-12-31. At its peak, it held 118.5K shares on 2026-03-31. Its highest holding value was $21.7M on 2026-03-31. At its lowest, it held 85.0K shares on 2025-12-31, with a value of $15.0M on 2025-12-31.